[9a-Z27-1~13] 11.2 Thin and thick superconducting films, coated conductors and film crystal growth

[9a-Z27-2] Characterization of Ion-Irradiated GdBa₂Cu₃O_7-δ Superconducting Tapes Using a Slow Positron Beam

〇Atsushi YABUUCHI¹, Atsushi KINOMURA¹, Toshinori OZAKI², Hitoshi SAKANE³, Hiroyuki OKAZAKI⁴, Hiroshi KOSHIKAWA⁴, Shunya YAMAMOTO⁴, Tetsuya YAMAKI⁴ (1.Kyoto Univ., 2.Kwansei Gakuin Univ., 3.SHI ATEX, 4.QST)

Keywords:superconductor, positron annihilation spectroscopy, vacancy-type defect

Ion-irradiated GdBa₂Cu₃O_7-δ superconducting tapes were probed by using a slow positron beam. The S parameter, which increases with increasing concentration and/or size of vacancy-type defects, was found to decrease with introducing irradiation-induced vacancies. This suggests that the size of the dominant positron trapping defects was reduced by ion irradiation. In other words, relatively large vacancy-type defects were implied to be present before the irradiation.